1. Field of the Invention
The present invention relates to a drying jig assembling apparatus, a drying jig disassembling apparatus, a drying jig circulating apparatus, a drying method of a ceramic molded body, and a method for manufacturing a honeycomb structure.
2. Discussion of the Background
In recent years, particulates such as soot contained in exhaust gases that are discharged from internal combustion engines of vehicles such as buses and trucks, and construction machines and the like, have raised serious problems as contaminants harmful to the environment and the human body.
Various honeycomb filters using honeycomb structures made from porous ceramic materials, which serve as filters that capture particulates in exhaust gases to purify the exhaust gases, have been proposed.
Conventionally, upon manufacturing such a honeycomb structure, first, a wet mixture is prepared by mixing ceramic powder, a binder and a dispersant solution or the like with one another. Moreover, the wet mixture is continuously extrusion-molded through a die, and the extruded molded body is cut into a predetermined length so that a pillar-shaped honeycomb molded body is manufactured.
Next, the resulting honeycomb molded body is dried by using a microwave drying method or a hot-air drying method.
Thereafter, the end portions of this honeycomb molded body are plugged by a plug material paste mainly composed of the ceramic powder into a diced pattern, and then respective degreasing and firing processes are carried out on the resulting honeycomb molded body so that a honeycomb fired body is manufactured.
Thereafter, a sealing material paste is applied to the side faces of the honeycomb fired body, and the honeycomb fired bodies are mutually bonded by using a adhesive so that an aggregate of the honeycomb fired bodies in which a number of the honeycomb fired bodies are combined with one another by interposing the sealing material layer (adhesive layer) is manufactured. Next, cutting is carried out on the resulting aggregate of the honeycomb fired bodies so that it is formed into a predetermined shape, such as a cylindrical shape and a cylindroid shape, by using a cutting machine or the like so that a honeycomb block is formed, and lastly, a sealing material paste is applied onto the periphery of the honeycomb block to form a sealing material layer (coat layer); thus, the manufacturing processes for the honeycomb structure are completed.
In such a manufacturing method of a honeycomb structure, JP-A 2001-130973 has disclosed a drying method in which: in order to prevent warping in the honeycomb molded body and cracks and the like in the cell walls from occurring upon drying a honeycomb molded body, a drying jig configured by an upper jig and a lower jig is used and the drying process is carried out with the honeycomb molded body being enclosed into a tightly contact state from above as well as from below with these upper and lower jigs.
Moreover, with respect to the drying method of a honeycomb molded body, WO 2005/024326 A1 has disclosed a method in which, in order to repeatedly use a tray on which the honeycomb molded body is mounted, the tray is circulated.
The contents of JP-A 2001-130973 and WO 2005/024326 A1 are incorporated herein by reference in their entirety.